Latchbolt holdback for doorlocks



April 21, 1964 M. P. BELLANTUONO 3,129,579

LATCHBOLT HOLDBAK FOR DOORLOCKS Filed Feb. l, 1962 '2 Sheets-Sheet l April 21, 1964 M. P. BELLANTUONO 3,129,579

LATCHBOLT HOLDBACK FOR DOORLOCKS 2 Sheets-Sheet 2 Filed Feb. l, 1962 m. w m m United States Patent 3,129,579 LATCHBLT HGLDBACK FOR DOORLOCKS Morris P. Bellantuono, Piainville, Conn., assigner to The American Hardware Corporation, New Britain, Conn., a corporation of Connecticut Filed Feb. 1, 1962, Ser. No. 170,348 18 Claims. (Ci. 70-107) This invention relates to novel latchbolt holdback means for door locks and more particularly to latchbolt holdback means for door locks of the mortise or rim type having a deadbolt in addition to a latchbolt.

The door locks for which the latchbolt holdback means of the present invention are especially intended generally comprise a casing which is adapted to be mortised into the free edge of a door or mounted on a face thereof adjacent said edge. A latchbolt is supported in said casing for reciprocable movement between a projected, latching position and a retracted, unlatehed position and said latchbolt is usually spring-pressed toward its projected position wherein it is engageable with a keeper on the door frame to retain the door in closed position.

The casing also contains rollback means Ifor retracting the latchbolt which are actuated by inner and outer door knobs or the like, and means may also be provided for locking the outer knob against operation to prevent retraction of the latchbolt from the outer side of the door. In this case, separate rollback means are generally provided in the casing for operation by key controlled means from the outer side of the door to permit retraction of the latchbolt when the outer knob is locked against operation.

A deadbolt may be mounted in the casing for reciprocable movement parallel to the latchbolt between a normally retracted position and a projected position wherein said deadbolt is engageable with the keeper on the door frame to lock the door in closed position. A cam is provided fin the casing for shifting the deadbolt between its retracted and projected positions and said cam is generally adapted to be operated by a turnpiece or the like which is accessible at the inner side of the door and by the aforementioned key controlled means from the outer side of the door.

In many instances, it is necessary or desirable to provide means in such locks for holding the latchbolt in retracted position to prevent engagement thereof with the keeper and thus permit free opening and closing movements of the door. This is particularly true when the locks are to be used on the doors of public buildings or the like which are subjected to frequent usage; not only does disablement of the latchbolt reduce wear and tear on the lock mechanism, but it also provides for facile passage through the doorway. However, in prior locks of the above-described type, and particularly those incorporating a deadbolt, the provision of latchbolt holdback means has presented a very considerable problem, due in part to the lack of available space in the lock casing for the holdback mechanism and to the necessity of making numerous changes in the regular lock casing to accommodate said mechanism.

It is therefore the primary object of the present invention to provide extremely novel latchbolt Iholdbaek means for door locks and particularly for door locks of the above-described type having a deadbolt in addition to a latchbolt.

Another object of the invention is to provide a latchbolt holdback mechanism which is designed to utilize many of the standard parts of conventional locks for its support and operation and for which the locks may be adapted with a minimum of changes.

A further object of the present invention is to provide novel latchbolt holdback means which are adapted to be ice carried on a standard part of a conventional lock and moved into and out of latchbolt holdback position through normal operation of said part.

A still further object of the present invention is to provide latchbolt holdback means which may be mounted on the deadbolt of a lock for cooperation with the latchbolt and other parts normally provided therein.

Another object of the present invention is to provide latchbolt holdback means which may be mounted on a conventional deadbolt so that locks may be provided with a holdback at assembly simply by substituting the deadbolt of the present invention for the ordinary deadbolt.

The foregoing and other objects and advantages of the invention will become apparent to those skilled in the art from the following description taken in connection with the accompanying drawings, which, by way of preferred example only, illustrate one specific embodiment of the invention.

In the drawings:

FIG. l is an elevational side view of a conventional mortise lock embodying my novel holdback means shown with the cover plate of the lock removed.

FIG. 2 is a similar view illustrating the positions occupied by the parts of the lock when both the latchbolt and the deadbolt are projected.

FIG. 3 is a similar view illustrating the manner in which the latchbolt holdback is moved to latchbolt holdback position.

FIG. 4 is a similar view illustrating the positions occupied by the parts of the lock when the latchbolt holdback member is in operative position.

FIG. 5 is a fragmentary elevational View illustrating the front of the lock.

FIG. 6 is an exploded isometric view 'further illustrating the parts of the lock shown in FIGS. 1 to 5 and the novel latchbolt holdback member of the present invention.

The door lock in which I have chosen to illustrate my novel latchbolt holdback means is of a conventional mortise type well known to thoseskilled in the art, and I have therefore illustrated only those parts of the lock which are germane to the present invention.

Referring now to the drawings, the numeral 5 denotes the casing of the lock which includes spaced, parallel, inner and outer sidewalls S-a and S-b, respectively, and an edge wall S-c; the sidewall S-a being in the form of a removable plate which is secured to the remainder of the casing by screws S-d and forms a cover plate for the lock mechanism. The casing also includes a face plate 6 which overlies the open edge thereof and is provided with spaced, longitudinally extending openings 7 and 7-a, as shown in FIG. 5

It will be understood by those skilled in the art that the casing is adapted to be mounted in a mortise formed in the edge of a door with the face plate 6 disposed flush with said edge, the casing being secured to the door by screws which extend through holes in the opposite end portions of the face plate, not shown.

'Ihe casing 5 contains a conventional lock mechanism which includes a latchbolt 8 that is mounted in said casing for reciprocable sliding movement between projected and retracted positions. The latchbolt includes a head portion -a which extends through and is slidably guided in the opening 7 in the face plate 6 and is provided at its outer end with a bevelled camming face S-b for engagement with a keeper on the door frame, not shown. The latchbolt also includes an elongated tailpiece 9 which extends axially rearwardly from the head portion S-a and is slidably guided in a slotted lug 10 projecting from the outer sidewall S-b of the lock case. The latchbolt is biased forwardly toward its normal projected position, as shown in full lines in FIG. 1, by a compression spring 11 which surrounds the tailpiece 9 and is disposed between the lug 1i) and the inner end of the latchbolt head 8-a.

The latchbolt 8 is moved rearwardly from its normal projected position to its retracted position through the operation of conventional rollback means indicated generally by the numeral 12 in FIG. 1. Said rollback means include a latchbolt retracting lever 13 which is pivoted at its lower end to the lock casing and has a free upper end disposed for engagement with the front face 14-a of a foot 14 that is fastened to the end of the tailpiece 9 and extends transversely and to the opposite sides thereof. The retracting lever 13 is adapted to be actuated by a rollback 15 which is mounted to rotate in the sidewalls of the casing and is provided with an axial bore 16 of polygonal cross-sectional shape for the reception of a spindle of complementary shape adapted to carry door knobs or the like at its inner and outer ends. The rollback is arranged to actuate the retracting lever 13 either directly or through a secondary operating lever 17 as best shown in FIG. 1. Thus, when the rollback is rotated in either direction, the lever 13 will be pivoted in a counterclockwise direction and will move the latchbolt 8 rearwardly from its normal projected position to its retracted position as shown in dotted lines in FIG. 1.

The lock mechanism also includes a deadbolt 18 which is mounted in the casing 5 for reciprocable movement in a direction parallel to the latchbolt 8. The deadbolt includes a head portion 18-a which is slidably guided in and adapted to extend through the opening 7-a in the face plate 6 and a tailpiece 18-b which extends rearwardly from the head portion 18-a and is slidably guided between the upper edge of the lug 1t) and the lower edge of a separate lug 19 which is formed on the outer sidewall of the lock case. The deadbolt is adapted to be shifted between its normal retracted position, shown in FIG. l, and its projected position, shown in FIG. 2, through the operation of a conventional cam 20 which is rotatably mounted in the sidewalls of the lock case and has a radial finger 21 adapted to engage the sides of a notch 22 in the tailpiece 18-1; of the deadbolt for shifting the deadbolt in one direction or the other. The upper portions of the sides of said notch are angled in opposite directions to provide clearance for the cam finger 21 and also to provide abutment surfaces on said tailpiece engageable by the end of said carn linger in the extreme positions of the cam for deadlocking the deadbolt in either its retracted position or its projected position as shown in FIGS. 1 and 2, respectively. In the particular lock illustrated, rotation of the cam 29 beas shown. In addition, means are provided for preventf ing unintentional movement of the cam 20 out of its said deadlocking positions. In this instance, said means comprise a leaf-spring 18-c which is mounted on the tailpiece 18-b of the deadbolt and is engageable with abutment surfaces formed on the cam finger 21 whereby to yieldingly retain the cam finger in engagement with said lugs.

The cam 20 is provided with an axial bore of polygonal cross-sectional shape which is adapted to receive a spindle extending from a turnpiece 23 that is mounted at the inner side of the lock casing and may be used to rotate the cam 20 for either projecting or retracting the deadbolt. The cam is also provided with a recess 24 for the reception of a lever 25 which is affixed to the inner end of a rotatable keyplug 26 forming part of a conventional lock cylinder 27 that is threaded into an opening in the outer sidewall 5-b of the lock case, said keyplug being accessible for operation by the proper key from the outer side of the door as will be evident from FIG. 5. The deadbolt may be moved from its retracted to its projected position by rotating the keyplug in a clockwise direction, as viewed in FIG. 1, or from its projected to its retracted position by rotating the keyplug in a counterclockwise direction as will be evident from FIG. 2. In either case, the lever 25 will enter the recess 24 and rotate the cam 20 in the proper direction.

The lock mechanism may also include means for dogging the rollback 15 against rotation to prevent retraction of the latchbolt 8 from the outer side of the door and a separate retracting lever which is operable by the key operated lever 25 to retract the latchbolt when said rollback is inoperable. These parts have not been shown in order to avoid unnecessarily complicating the drawings, but the construction and operation thereof are conventional and will be understood by those familiar with the art.

I have provided by my invention latchbolt holdback means which are especially adapted for use in locks of the above-described type for holding the latchbolt in retracted position to permit free opening and closing movements of the door. As an extremely novel feature of my invention, I utilize the deadbolt 1S of the lock as a carrier member for the latchbolt holdback member and have so designed the mechanism that very few structural changes are required in the deadbolt. In fact, so few structural changes are necessary that the deadbolt incorporating my novel latchbolt holdback mean-s may be substituted for the ordinary deadbolt of the lock without making any changes in the lock casing.

The latchbolt holdback means of the present invention includes a holdback member 28 which, as best shown in FIG. 6, may be formed from sheet metal and has a body portion 29 containing an aperture 3i) therethrough and a stop portion 31 extending rearwardly of said aperture. A leg 32 extends downwardly and outwardly from said body portion and has an elongated finger 33 extending rearwardly therefrom parallel to said body portion. A spring abutment 34 is formed on the upper edge of said body portion and extends to the opposite side thereof from the finger 33.

The latchbolt holdback member 28 is pivotally mounted on the tailpiece 18-b of the deadbolt by a pin 35 which extends laterally from said tailpiece and is received in the aperture 30. When so mounted, the linger 33 on said holdback member extends rearwardly relatively to the latchbolt and the free end 33-a of said finger is opposed to the front surface )L4-cz on the foot 1d at the inner end of said latchbolt. rIhe holdback member 28 is biased in a counterclockwise direction toward latchbolt holdback position by a torsion spring 36 which is mounted on said pin 3S and has one end engaging the spring abutment 34 and its opposite end engaging a lateral projection 37 on the tailpiece 1S-b of the deadbolt, the projection 37 also being disposed for engagement by the stop portion 31 on the holdback member to limit counterclockwise movement thereof under the inuence of the spring 36.

Referring now to FIG. l of the drawing, it will be seen that when the deadbolt 18 is in its normal retracted position, the latchbolt holdback member 28 is retained out of latchbolt holdback position against the bias of the spring 36 through engagement of the lower edge of the finger 33 with the upper edge of the foot 14 on the inner end of the latchbolt, said upper edge providing a stop surface 14-b on said foot which is opposed to said finger and extends rearwardly from the edge of the front surface 14-11 in a direction substantially parallel to the direction of movement of the latchbolt. Thus, as the latchbolt moves between its projected and retracted positions, the stop surface it-b on said foot 14 will slide along the finger 33 and will prevent it from moving into the path of the foot 14, it being noted that the finger 33 is of such length that it will extend rearwardly of the front surface 11i-a of said foot when the latchbolt is in its fully retracted position, as shown in dotted lines in FIG. l. It will thus be apparent that when the deadbolt is retracted, the latchbolt holdback member 28 will at all times be maintained out of latchbolt holdback position by the stop surface on the foot 14 to permit normal operation of the latchbolt.

Referring now to FIG. 2 of the drawing, it will be seen that when the deadbolt is moved from retracted to projected position through operation of either the turnpiece 23 or the key-operated lever 25, the holdback member 28 is maintained out of latchbolt holdback position through engagement of the nger 33 with a cam surface Iii-a provided on the upper edge of the slotted lug 10. During the initial movement of the deadbolt from retracted to projected position, the holdback member is held out of latchbolt holdback position through engagement of the finger 33 with the stop surface 14-b on the foot 14 over which it slides. However, at an intermediate position of the deadbolt, the finger 33 will engage the cam surface -a on the slotted lug 10, this engagement taking place before the free end of said finger passes the front edge of said stop surface, and said finger will thereafter be supported by said lug as the deadbolt moves to its fuliy projected position shown in FIG. 2.

When it is desired to maintain the latchbolt in retracted position to permit free opening and closing movements of the door, it is only necessary to move the latchbolt to its retracted position, as indicated in dotted lines in FIG. l, either by pushing the latchbolt inwardly or by operating the rollback means l2. The cam is then rotated through actuation of the turnpiece 23 or the key-operated lever 25 to shift the deadbolt toward its projected position. As the deadbolt moves forwardly the free end of the finger 33 on the latchbolt holdback member will ride off the front edge of the stop surface on the foot I4. The spring 36 will then pivot the holdback member in a counterclockwise direction and into latchbolt holdback position, as determined by engagement of the stop portion 31 with the projection 37, wherein the free end of said finger is disposed for engagement with the front surface 141-51 of the foot 14 as shown in FIG. 3. The deadbolt is then returned to it normal retracted position and the holdback member will thereafter retain the latchbolt in retracted position against the force of the spring 1i. Although the force of the spring 11 is transmitted to the deadbolt through the latchbolt holdback member, the deadbolt is prevented from moving to projected position by the cam 20 which is disposed in normal deadlocking relationship thereto, all as shown in FIG. 4.

It will be noted that because the pivotal axis of the holdback member 28 is disposed above the longitudinal axis of the latchbolt 8, the free end 33-a of the finger 33 will move forwardly with respect to the latchbolt as the holdback member swings into latchbolt holdback position. In other words, when the holdback member 23 is in hoidback position, the free end of said finger is disposed forwardly of the position which it occupies when the holdback member is in its normal position. The arrangement is such that the forward movement of the free end of said finger compensates for the movement of the deadbolt required to disengage said finger from the stop surface 14 b and thereby permits the deadbolt to be returned to its fully retracted position when the holdback member is in holdback position.

The latchbolt holdback member 28 may be returned to its normal position to release the latchbolt by moving the deadbolt toward its projected position. This will cause the finger 33 to engage the cam surface 10-a on the upper edge of the lug 1i) and to be lifted thereby out of engagement with the foot I4 on the latchbolt. As soon as the latchbolt is released, the spring 11 will urge it into projected position to permit operation of the lock in the normal manner as above-described.

While I have illustrated herein a preferred embodiment of the present invention, it will be apparent to those skilled in the art that numerous modifications and changes may be made therein and that it is not desired to limit the invention to the exact construction and operation shown 6 and described. Accordingly, all suitable modifications and equivalents may be resorted to that fall within the scope of the invention as claimed.

What is claimed as new is as follows:

1. In a door lock including a latchbolt movable between a projected, latching position and a retracted, unlatched position, spring means biasing said latchbolt toward projected position and an abutment on said latchbolt; the combination of: a holdback member movable between a normal position clear of said abutment and a latchbolt holdback position engaged with said abutment when said latchbolt is retracted for holding said latchbolt in retracted position against the bias of said spring means, means biasing said holdback member toward latchbolt holdback position, stop means for retaining said holdback member out of latchbolt holdback position to permit normal operation of said latchbolt, said holdback member being movable relatively to said stop means to permit disengagement thereof from said stop means and movement of said holdback member into latchbolt holdback position under the influence of said biasing means, and means for so moving said holdback member.

2. In a door lock including a latchbolt movable between a projected, latching position and a retracted, unlatched position, spring means biasing said latchbolt toward projected position and an abutment on said latchbolt; the combination of: a holdback member movable between a normal position clear of said abutment and a latchbolt holdback position engaged with said abutment when said latchbolt is retracted for holding said latchbolt in retracted position against the bias of said spring means, cam means fixedly mounted in said lock for camming said holdback member out of latchboit holdback position, said holdback member being movable relatively to and into engagement with said cam means to effect disengagement thereof from said abutment, and operating means for so moving said holdback member.

3. In a door lock including a latchbolt movable between a projected, latching position and a retracted, unlatched position, spring means biasing said latchbolt toward projected position and an abutment on said latchbolt; the combination of: a holdback member movable between a normal position clear of said abutment and a latchbolt holdback position engaged with said abutment when said latchbolt is retracted for holding said latchbolt in retracted position against the bias of said spring means, means biasing said holdback member toward latchbolt holdback position, stop means for retaining said holdback member out of latchbolt holdback position to permit normal operation to said latchbolt, said holdback member being movable out of engagement with said stop means to effect movement thereof into latchbolt holdback position under the inuence of said biasing means, cam means for camming said holdback member out of latchbolt holdback position, said holdback member also being movable into engagement with said cam means to effect disengagement thereof from said abutment, and operating means for moving said holdback member relatively to said stop means and said cam means.

4. In a door lock including a latchbolt movable between a projected, latching position and a retracted, unlatched position, spring means biasing said latchbolt toward projected position and an abutment on said latchbolt; the combination of: a holdback member movable in a first direction between a normal position clear of said abutment and a latchbolt holdback position engaged with said abutment when said latchbolt is retracted for holding said latchbolt in retracted position against the bias of said spring means, means biasing said holdback member toward latchbolt holdback position, stop means for retaining said holdback member out of latchbolt holdback position against the influence of said biasing means to permit normal operation of said latchbolt, said holdback member being movable in a second direction relatively to said stop means to effect disengagement of said holdback Zi member from said stop means and movement of said holdback member into latchbolt holdback position, and operating means for moving said holdbaek member in said second direction.

5. In a door lock including a latchbolt movable between a projected, latching position and a retracted, unlatched position, spring means biasing said latchbolt toward projected position and an abutment on said latchbolt; the combination of: a holdback member movable in a iirst direction between a normal position clear of said abutment and a latchbolt holdbaci: position engaged with said abutment when said latchbolt is retracted for holding said latchbolt in retracted position against the bias of said spring means, cam means for camming said holdbaci: member out of latchbolt holdback position, said holdback member being movable in a second direction into engagement with said cam means to eect disengagement thereof from said abutment, and operating means for moving said holdback member in said second direction.

6. In a door lock including a latchbolt movable between a projected, latching position and a retracted, unlatched position, spring means biasing said latchbolt toward projected position and an abutment on said latchbolt; the combination of: a holdback member movable in a rst direction between a normal position clear of said abutment and a latchbolt holdback position engaged with said abutment when said latchbolt is retracted for holding said latchbolt in retracted position against the bias of said spring means, means biasing said holdback member toward latchbolt holdback position, stop means for retaining said holdback member out of latchbolt holdback position against the intiuence of said biasing means to permit normal operation of said latchbolt, cam means for camming said holdback member out of latchbolt holdback position, said holdback member being movable in a second direction relatively to said stop means and said cam means for effecting movement thereof into and out of latchbolt holdback position, and operating means for moving said holdback member in said second direction.

7. ln a door lock including a latchbolt movable between a projected, latching position and a retracted, unlatched position, spring means biasing said latchbolt toward projected position and an abutment on said latchbolt; the combination of: a carrier member movabie relatively to said latchbolt, a holdback member mounted on said carrier member for movement relatively thereto between a normal position clear of said abutment and a latchbolt holdback position engaged with said abutment when said latchbolt is retracted for holding said latchbolt in retracted position against the bias of said spring means, means biasing said holdbaclf. member toward latchbolt holdback position, stop means engageable by said holdback member for retaining said holdback member out of latchbolt holdbacl; position, said carrier member being movable to carry said holdback member out of engagement with said stop means to permit movement of said holdback member into latchbolt 'holdback position under the iniluence of said biasing means, and means for moving said carrier member.

8. The subject matter set forth in claim 7 including cam means for camming said holdback member out of latchbolt holdback position, said carrier member being movable to carry said holdback member into engagement with said cam means to effect disengagement thereof from said abutment.

9. In a door lock including a latchbolt movable between a projected, latching position and a retracted, unlatched position, spring means biasing said latchbolt toward projected position and an abutment on said latchbolt; the combination of: a carrier member movable relatively to said latchbolt, a holdback member pivotaliy mounted on said carrier member for movement relatively thereto between a normal position clear of said abutment and a latchbolt holdback position engaged with said abutment when said latchbolt is retracted for holding said latchbolt in retracted position against me bias of said spring means, a separate spring biasing said holdback member toward latchboit holdbacit position, stop means for retaining said holdback member out of latchboit holdback position, said carrier member being movable to shift said holdback member out of engagement with said stop means to permit movement thereof into latchbolt holdback position under the inuence of said separate spring means, cam means for camming said holdback member out of latchbolt holdback position, said carrier member being movable to carry said holdback member into engagement with said cam means for effecting disengagement thereof from said abutment, and operating means for moving said carrier member.

10. The subject matter set forth in claim 9 wherein said stop means comprises a surface on said latchbolt.

l1. The subject matter set forth in claim 9 wherein said operating means includes a key operated element,

12. In a door lock including a casing, a latchbolt mounted in said casing for movement between a projected, latching position and a retracted, unlatched position, a spring biasing said latchbolt toward projected position, an abutment on said latchbolt, a deadbolt mounted in said casing for movement relatively to said latchbolt between retracted and projected positions and manually operable means for moving said deadbolt between its said positions; the combination of: a holdback member mounted on said deadbolt for movement between a normal position ciear of said abutment and a latchbolt holdback position engaged with said abutment when said latchbolt is retracted for holding said latchbolt in retracted position against the bias of said spring means, means biasing said holdbaclr member toward latchbolt holdback position, stop means engageable by said holdback member when said deadbolt is retracted for retaining said holdback member out of latchbolt holdback position against the influence of said biasing means, said holdback member being disengageable from said stop means and movable into latchbolt holdback position upon movement of said deadbolt toward projected position, and cam means for camming said holdback member out of latchbolt holdback position, said holdback member being movable into engagement with said cam means upon movement of said deadbolt toward projected position to eect disengag ment thereof from said abutment.

13. The subject matter set forth in claim 12 wherein said latchbolt holdback member is pivotally mounted on said deadbolt for movement into and out of latchbolt holdback position and a spring is interposed between said holdback member and said deadbolt for urging said holdback member toward latchbolt holdback position.

14. The subject matter set forth in claim 13 wherein said latchbolt holdback member is provided with a stop portion engageable with a portion on said deadbolt for limiting movement of said holdback member to latchbolt holdback position under the influence of said spring.

15. In a door lock including a casing, a latchbolt mounted in said casing for reciprocable movement along its longitudinal axis between a forward projected position and a rearward retracted position, spring means biasing said latchbolt toward projected position, an abutment on said latchbolt having an abutment surface at the front thereof extending transversely of said axis and a stop surface adjacent said abutment surface extending rearwardly therefrom substantially parallel to said axis, a deadbolt mounted in said casing for reciprocable movement substantially parallel to said latchbolt between a retracted position and a projected position, and manually operable means for moving said deadbolt between its said positions; the combination of: a holdback member including a body portion pivotally mounted on said deadbolt and an elongated finger extending rearwardly from said body portion and having a free end opposed to said abutment surface, said holdback member being pivotally movable about .an axis extending transversely of the longitudinal axis of said latchbolt between a normal position wherein the free end of said finger is disposed clear of said abutment surface and a latchbolt holdback position wherein said free end is disposed in the path of said abutment surface, a spring biasing said holdback member toward latchbolt holdback position,

said nger being engageable with said stop surface when said deadbolt is retracted to prevent movement of said holdback member into latchbolt holdback position during normal projection and retraction of said latchbolt, said nger being movable out of engagement with said stop surface when said deadbolt is moved toward projected position with said latchbolt in retracted position to permit movement of said holdback member into latchbolt holdback position wherein the free end of said finger is engaged with said abutment surface to retain said latchbolt in retracted position, and cam means in said casing disposed for engagement by said finger upon movement of said deadbolt toward projected position for camming said linger out of engagement with said abutment surface to permit projection of said latchbolt.

16. The subject matter set forth in claim l wherein the pivotal axis of said holdback member is so located with respect to the longitudinal axis of said latchbolt that, as said holdback member pivots from its normal to its latchbolt holdback position, the free end of said finger moves axially outwardly with respect to said latchbolt axis a distance at least equal to the distance the deadbolt must be moved to effect disengagement of said linger from said stop surface, whereby to permit said deadbolt to be returned to its normal retracted position when said holdback member is disposed in latchbolt holdback position.

17. In a door lock including a latchbolt movable between a projected, latching position and a retracted, unlatched position, spring means biasing said latchbolt toward projected position and an abutment surface on said latchbolt; the combination of: a carrier member, a latchbolt holdback member having a detent portion opposed to said abutment surface, said holdback member being mounted on said carrier member for movement between a normal position in which said detent portion is disposed clear of said abutment surface and a latchbolt holdback position in which said detent portion is disposed in the path of said abutment surface for holding said latchbolt in retracted position, a spring biasing said holdback member toward latchbolt holdback position, a stop Surface on said latchbolt adjacent said abutment surface engageable by said holdback member to prevent movement thereof into latchbolt holdback position, said carrier member being movable from a normal position wherein said holdback member is engaged with said stop surface to a release position wherein said holdback member is disengaged from said stop surface to permit movement of said holdback member into latchbolt holdback position under the influence of said spring, said holdback member being so arranged on said carrier member that as it moves into latchbolt holdback position said detent portion is displaced an amount suicient to permit said carrier member to return to its normal position when said detent is engaged with said abutment surface.

18. In a door lock including a casing, a latchbolt mounted in said casing for reciprocable movement along its longitudinal axis between a forward, projected position and a rearward, retracted position, spring means biasing said latchbolt toward projected position and an abutment on said latchbolt including a forwardly facing abutment surface extending transversely of said axis and a stop surface extending rearwardly from said abutment surface substantially parallel to said axis; the combination of: a carrier member mounted in said casing for movement relatively to said latchbolt between a rst position and a second position, a latchbolt holdback member mounted on said carrier member for pivotal movement relatively thereto about an axis spaced from the longitudinal axis of said latchbolt and extending transversely thereto, said carrier member being arranged to move said holdback member in generally the same direction as said latchbolt moves, said holdback member having a finger portion provided with a free end opposed to said abutment surface and being pivotally movable between a normal position wherein said free end is disposed clear of said abutment surface and a latchbolt holdback position wherein said free end is disposed in the path of said abutment surface, a spring biasing said holdback member toward latchbolt holdback position, said finger being engageable with said stop surface when said carrier member is in its said lirst position to prevent movement of said latchbolt holdback member into latchbolt holdback position during normal retraction and projection of said latchbolt, said nger being movable out of engagement with said stop surface when said carrier member is moved toward its said second position with said latchbolt in retracted position to permit movement of said holdback member into latchbolt lholdback position under the influence of said spring, the free end of said finger moving axially outwardly with respect to said latchbolt as said holdback member moves into latchbolt holdback position to compensate for the movement of said carrier member necessary to disengage said nger from said stop surface, whereby to permit the return of said carrier member to its said rst position when said holdback member is in latchbolt holdback position.

Hurd Aug. 3, 1937 Chobert Jan. 5, 1954 

1. IN A DOOR LOCK INCLUDING A LATCHBOLT MOVABLE BETWEEN A PROJECTED, LATCHING POSITION AND A RETRACTED, UNLATCHED POSITION, SPRING MEANS BIASING SAID LATCHBOLT TOWARD PROJECTED POSITION AND AN ABUTMENT ON SAID LATCHBOLT; THE COMBINATION OF: A HOLDBACK MEMBER MOVABLE BETWEEN A NORMAL POSITION CLEAR OF SAID ABUTMENT AND A LATCHBOLT HOLDBACK POSITION ENGAGED WITH SAID ABUTMENT WHEN SAID LATCHBOLT IS RETRACTED FOR HOLDING SAID LATCHBOLT IN RETRACTED POSITION AGAINST THE BIAS OF SAID SPRING MEANS, MEANS BIASING SAID HOLDBACK MEMBER TOWARD LATCHBOLT HOLDBACK POSITION, STOP MEANS FOR RETAINING SAID HOLDBACK 